from pathlib import Path
import json
import py_compile
import sys
from PIL import Image

ROOT = Path(__file__).resolve().parent
REQUIRED = [
    'app.py', 'requirements.txt', 'packages.txt', 'README.md',
    'template.jpg', 'template_lossless.png', 'template.json',
    'marker_config.json', 'template_A4_print.pdf', 'marker_reference.png',
    'samples/sample_phone_perspective.jpg',
    'samples/sample_phone_shadow_rescue.jpg',
    'samples/sample_phone_missing_tl.jpg',
]
errors = []

for filename in REQUIRED:
    if not (ROOT / filename).is_file():
        errors.append(f'Missing: {filename}')

try:
    py_compile.compile(str(ROOT / 'app.py'), doraise=True)
except Exception as error:
    errors.append(f'app.py syntax validation failed: {error}')

for image_name in ('template.jpg', 'template_lossless.png'):
    try:
        image = Image.open(ROOT / image_name)
        if image.size != (3093, 4374):
            errors.append(f'{image_name} size is {image.size}, expected (3093, 4374)')
    except Exception as error:
        errors.append(f'{image_name} cannot be read: {error}')

try:
    template = json.loads((ROOT / 'template.json').read_text(encoding='utf-8'))
    markers = json.loads((ROOT / 'marker_config.json').read_text(encoding='utf-8'))
    if template.get('pageDimensions') != [3093, 4374]:
        errors.append('template.json pageDimensions mismatch')
    if markers.get('pageDimensions') != [3093, 4374]:
        errors.append('marker_config.json pageDimensions mismatch')
    if markers.get('largeMarkerOuterSize') != 144:
        errors.append('V3.1 largeMarkerOuterSize must remain 144')
    if markers.get('strictMarkerMode') is not True:
        errors.append('strictMarkerMode must default to true')
    if 'smallGroupMarkers' in markers or 'smallMarkerOuterSize' in markers:
        errors.append('Small group marker settings must not exist in this variant')
    rescue = markers.get('localRescue') or {}
    if rescue.get('enabled') is not True:
        errors.append('V3.1 localRescue.enabled must be true')
    if int(rescue.get('minimumGlobalCandidates', 0)) < 2:
        errors.append('minimumGlobalCandidates must be at least 2')
    if int(rescue.get('maxRescueCorners', 99)) > 2:
        errors.append('maxRescueCorners must not exceed 2')
    threshold = float(rescue.get('templateMatchThreshold', 0))
    if not 0.35 <= threshold <= 0.65:
        errors.append('templateMatchThreshold outside expected safe range')
except Exception as error:
    errors.append(f'JSON validation failed: {error}')

if errors:
    print('PROJECT VALIDATION FAILED')
    for error in errors:
        print('-', error)
    sys.exit(1)

print('PROJECT VALIDATION PASSED')
print('V3.1 four-large-marker-only template, local-shadow rescue settings and required files are present.')